Thiosilanes in sulfur chemistry: A general approach to silyl thiaheterocycles and their use in stereoselective synthesis

2-Silyl five-membered sulfurated heterocycles can be efficiently accessed through reaction of bromo(methoxy)methyl trimethylsilane with suitable β-substituted mercaptans HS-CH2CH2-XH, leading to the formation of 2-silyl-1,3-dithiols, 2-silyl-1,3-thiazolidines, and 2-silyl-1,3-oxathiolanes. β-Mercaptoalcohols are obtained through regioselective ring opening of epoxides with bis(trimethylsilyl)sulfide (HMDST). In a similar way, thiiranes and aziridines react with HMDST, leading to the formation of 1,2-dithiols and β-aminothiols. Fluoride ion induced functionalization of the pentaatomic heterocycles smoothly affords the transfer of the heterocyclic ring on electrophiles, thus showing these silyl derivatives as a new class of acyl anion equivalents. When stereodefined compounds are reacted, the stereoinformation is transferred from the carbon–silicon to the newly formed carbon–carbon bond. © 2007 Wiley Periodicals, Inc. 18:516–526, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20345